Could you please tell me why the article ‘a’ has been used in the following sentences? Since ‘second’ and ‘last’ are particular and the listener knows which ones, perhaps, it should be ‘the’.
1- Give me a second chance. (Does it sound OK?)
2- This method is a last resort.(Why not the?)
Both of your sentences are perfect with “a”.
Maybe you could look at it this way:
1/ “A second chance” basically means “another chance” or “one more chance”
You could also say: “a third chance” / “a fourth chance” / “a final chance” / etc.
2/ “A last resort” is a possible course of action that could be used to solve or settle a problem. It is a course of action that is usually much less than optimal and therefore would not be among the first choices as a course of action.